Area lighting devices and methods

Abstract

The present application discloses, among other things, optics and lighting devices, systems, and associated methods for delivering light asymmetrically onto a target surface so as to create a desired illumination pattern. Typically, the optics and lighting systems described herein include an optic that receives light from one or more light sources and redirects the light in a patterned or other controlled manner. In many cases, a central lens portion can generate a desired asymmetric illumination pattern while peripheral lens portions redirect light received from the light source to portions of the asymmetric illumination pattern generated by the central lens portion. In many embodiments, the central lens portion redirects light received from a source only via refraction, whereas the peripheral lens portions redirect the light received from the source via a combination of reflection and refraction.

What is claimed is: 
     
         1 . An optic comprising:
 an input surface adapted for receiving light from a light source,   an output surface having a central portion and a pair of side portions, and   a pair of reflective sidewalls,   said central portion of the output surface being positioned relative to said input surface and having a surface profile such that it refracts light incident thereon via the input surface asymmetrically out of the optic,   wherein each of said reflective sidewalls is adapted to reflect light incident thereon via the input surface to a respective one of said side portions of the output surface for exiting the optic.   
     
     
         2 . The optic of  claim 1 , wherein said input surface exhibits rotational symmetry about an axis (“central axis”). 
     
     
         3 . The optic of  claim 2 , wherein said optic exhibits a plane of symmetry and said central axis lies in said plane of symmetry. 
     
     
         4 . The optic of  claim 3 , wherein light rays exiting the central portion of the output surface in said plane of symmetry diverge asymmetrically relative to said central axis. 
     
     
         5 . The optic of  claim 3 , wherein light rays exiting the optic through the central portion of the output surface in said plane of symmetry exhibit a maximum divergence angle relative to the central axis on one side of the central axis that is different from a respective maximum divergence angle relative to the central axis on an opposed side of the central axis. 
     
     
         6 . The optic of  claim 5 , wherein a maximum divergence angle relative to the central axis of light rays exiting the central portion of the output surface in the plane of symmetry on one side of the central axis is equal to or greater than an angular divergence angle of light rays exiting the optic in said plane of symmetry through a side portion of the output surface located on an opposed side of the central axis. 
     
     
         7 . The optic of  claim 3 , wherein a maximum divergence angle relative to the central axis of light rays exiting the optic in said plane of symmetry is less than a maximum divergence angle relative to the central axis of the light rays exiting the optic in another plane (“second plane”) that contains the central axis and is perpendicular to said plane of symmetry. 
     
     
         8 . The optic of  claim 7 , wherein said optic is asymmetric about said second plane. 
     
     
         9 . The optic of  claim 8 , wherein light rays exiting the central portion of the output surface in said second plane diverge symmetrically relative to said central axis. 
     
     
         10 . The optic of  claim 9 , wherein light rays in the second plane exhibit a maximum divergence angle relative to the central axis of about 70 degrees on each side of the central axis. 
     
     
         11 . The optic of  claim 3 , wherein the pair of reflective sidewalls comprises first and second sidewalls, and wherein an angular divergence of light received by the first sidewall from the input surface in the plane of symmetry is less than an angular divergence of light received by the second sidewall from the input surface in the plane of symmetry. 
     
     
         12 . The optic of  claim 11 , wherein a minimum distance between the first sidewall and the central axis is greater than a minimum distance between the second sidewall and the central axis in the plane of symmetry. 
     
     
         13 . The optic of  claim 11 , wherein the side portions associated with the first and second sidewalls intersect the central portion of the output surface at an intersection point, and wherein the minimum distance between the central axis and the intersection point on one side of the central axis is greater than on the opposed side of the central axis. 
     
     
         14 . The optic of  claim 11 , wherein said central portion of the output surface is positioned relative to the input surface such that a majority of light rays in the plane of symmetry incident on the central portion of the output surface is refracted toward one side of the central axis relative to the other side. 
     
     
         15 . The optic of  claim 11 , wherein said central portion of the output surface is positioned relative to the input surface such that light rays in the plane of symmetry exit said central portion of the output surface at an angle relative to the central axis in a range of about 0 degree to about 60 degrees on a first side of the central axis and from about 0 degree to about 20 degrees relative to the central axis on a second side of the central axis. 
     
     
         16 . The optic of  claim 15 , wherein the side portion of the output surface associated with the sidewall on said first side of the central axis (“first side output surface”) is configured such that light rays in the plane of symmetry exiting said first side output surface exhibit an angular divergence of about 20 degrees. 
     
     
         17 . The optic of  claim 15 , wherein the side portion of the output surface associated with the sidewall on said second side of the central axis (“second side output surface”) is configured such that light rays in the plane of symmetry exiting said second side output surface exhibit an angular divergence of about 60. 
     
     
         18 . The optic of  claim 1 , wherein the reflective sidewalls are configured to reflect light incident thereon via total internal reflection. 
     
     
         19 . The optic of  claim 1 , wherein the reflective sidewalls are configured to reflect light incident thereon via specular reflection. 
     
     
         20 . The optic of the  claim 19 , wherein the reflective sidewalls are metalized. 
     
     
         21 . The optic of  claim 1 , wherein optic comprises a unitary structure. 
     
     
         22 . The optic of  claim 21 , wherein said optic is formed at least partially of one of polymethyl methacrylate (PMMA), glass, polycarbonate, cyclic olefin copolymer and cyclic olefin polymer. 
     
     
         23 . The optic of  claim 1 , wherein said central portion of the output surface comprises a surface having two lobes. 
     
     
         24 . The optic of  claim 1 , wherein said side portions of the output surface are substantially planar. 
     
     
         25 . The optic of  claim 3 , wherein one of said side portions forms an angle in the plane of symmetry in a range of about 50 degrees to about 70 degrees relative to said central axis and the other of said side portions forms an angle in a range in the plane of symmetry of about 30 degrees to about 10 degrees relative to said central axis. 
     
     
         26 . The optic of  claim 25 , wherein one of said side portions forms an angle in the plane of symmetry of about 60 degrees relative to said central axis and the other of said side portions forms and angle in the plane of symmetry of about 20 degrees relative to said central axis. 
     
     
         27 . The optic of  claim 1 , wherein said input surface lacks rotational symmetry. 
     
     
         28 . An optical system comprising:
 a light source, and   an optic having an inferior surface, a superior surface, and a pair of sidewalls extending therebetween,   wherein the inferior surface comprises an input portion for receiving light from the light source, the input portion forming a cavity for housing the light source,   wherein the superior surface comprises a central portion and two side portions, said central portion of the superior surface being adapted to refract at least a portion of the light received through the input portion out of the optic so as to generate an asymmetric illumination area on a target surface, and   wherein the sidewalls are adapted to reflect at least a portion of the light received through the input portion to a respective side portion of the superior surface such that each side portion of the superior surface refracts light incident thereon out of the optic to said asymmetric illumination area.   
     
     
         29 . The system of  claim 28 , wherein said optic comprises a unitary structure. 
     
     
         30 . The system of  claim 28 , wherein said side portions of the superior surface are planar. 
     
     
         31 . The system of  claim 28 , wherein the side portions of the superior surface have different surface areas. 
     
     
         32 . The system of  claim 28 , wherein said light source emits light characterized by a central propagation axis. 
     
     
         33 . The system of  claim 32 , wherein said optic exhibits a plane of symmetry and said central propagation axis lies in a plane through which the optic exhibits minor symmetry (“a plane of symmetry”). 
     
     
         34 . The system of  claim 33 , wherein said side portions of the superior surface are substantially planar. 
     
     
         35 . The system of  claim 34 , wherein said side portions of the superior surface have different angles in said plane of symmetry relative to said central propagation axis. 
     
     
         36 . The system of  claim 33 , wherein a minimum distance between one side portion of the superior surface and the central propagation axis is greater than a minimum distance between the other side portion of the superior surface and the central propagation axis. 
     
     
         37 . The system of  claim 33 , the optic is configured such that light rays exiting the optic through the central portion of the superior surface diverge asymmetrically relative to said central propagation axis. 
     
     
         38 . The system of  claim 33 , the optic is configured such that light rays exiting the optic through the central portion of the superior surface in said plane of symmetry exhibit a maximum divergence angle relative to the central propagation axis on one side of the central propagation axis that is different from a maximum divergence angle relative to the central propagation axis on an opposed side of the central propagation axis. 
     
     
         39 . The system of  claim 33 , the optic is configured such that a maximum divergence angle relative to the central propagation axis of light rays exiting the optic through the central portion of the superior surface in the plane of symmetry on one side of the central propagation axis is equal to or greater than an angular divergence of light rays exiting the optic through a side portion of the superior surface that is located on an opposed side of the central propagation axis. 
     
     
         40 . The system of  claim 33 , the optic is configured such that a maximum divergence angle relative to the central propagation axis of light rays exiting the optic through said superior surface in said plane of symmetry is less than a maximum divergence angle relative to the central propagation axis of the light rays exiting the optic through said superior surface in another plane (“second plane”) that contains the central propagation axis and is perpendicular to said plane of symmetry. 
     
     
         41 . The system of  claim 40 , wherein said optic is asymmetric about said second plane. 
     
     
         42 . The system of  claim 41 , wherein light rays exiting the central portion of the superior surface in said second plane diverge symmetrically relative to said central propagation axis in the second plane. 
     
     
         43 . The system of  claim 33 , wherein the optic is positioned relative to the light source such that a majority of light rays exiting the optic in the plane of symmetry are preferentially refracted away from the central propagation axis and toward one side of the central propagation axis relative to the other side. 
     
     
         44 . The system of  claim 28 , wherein said input surface exhibits rotational symmetry about an axis (“central axis”). 
     
     
         45 . The system of  claim 44 , wherein said light source emits light characterized by a central propagation axis and wherein said central axis and said central propagation axis are aligned. 
     
     
         46 . The system of  claim 44 , wherein the minimum distance between one side portion of the superior surface and the central axis is greater than a minimum distance between the other side portion of the superior surface and the central axis. 
     
     
         47 . A lighting system, comprising:
 a pole disposed adjacent a target surface, and   at least one lighting module mounted on said pole, the lighting module comprising a light source and a optic for directing light from said source to said target surface,   wherein the optic comprises a central refractive portion and a pair of side portions, the central refractive portion having a cavity for at least receiving said light source and for coupling light from said light source into said optic,   said central refractive portion further having an output surface adapted to refract at least a portion of light received through the input surface out of the optic so as to generate an asymmetric illumination area on said target surface,   wherein each of the side portions is adapted to redirect via reflection and refraction at least portion of the light received through the input surface out of the optic to said asymmetric lighting area.   
     
     
         48 . The system of  claim 47 , wherein the module is mounted such that one of said side portions (“proximal side portion”) is disposed proximal to said pole and the other of said side portions (“distal side portion”) is disposed distal to the pole. 
     
     
         49 . The system of  claim 47 , wherein said light source emits light characterized by a central propagation axis. 
     
     
         50 . The system of  claim 49 , wherein said module is mounted such that said central propagation axis is substantially parallel with a central longitudinal axis of the pole. 
     
     
         51 . The optic of  claim 49 , wherein said optic exhibits a plane of symmetry and said central propagation axis lies in said plane of symmetry. 
     
     
         52 . The optic of  claim 51 , the optic is configured such that light rays exiting the output surface of said central refractive portion in said plane of symmetry diverge asymmetrically relative to said central propagation axis. 
     
     
         53 . The optic of  claim 51 , the optic is configured such that light rays exiting said output surface of the central refractive portion in said plane of symmetry exhibit a maximum divergence angle relative to the central propagation axis on a distal side of said central propagation axis that is greater than a maximum divergence angle relative to the central propagation axis on a proximal side of said central propagation axis. 
     
     
         54 . The system of  claim 53 , wherein the proximal side portion comprises a proximal sidewall and a proximal output surface and the distal side portion comprises a distal sidewall and a distal output surface. 
     
     
         55 . The system of  claim 54 , wherein said proximal sidewall is configured such that substantially all light received from the input surface at the proximal sidewall is reflected to exit the optic through the proximal output surface. 
     
     
         56 . The system of  claim 55 , wherein a maximum divergence angle relative to the central propagation axis of light rays exiting said output surface of the central refractive portion in said plane of symmetry on said distal side of the central propagation axis is equal to or greater than an angular divergence of light rays exiting the proximal output surface in said plane of symmetry. 
     
     
         57 . The system of  claim 54 , wherein said distal sidewall is configured such that substantially all light received from the input surface at the distal sidewall is reflected to exit the optic through the distal output surface. 
     
     
         58 . The system of  claim 57 , wherein a maximum divergence angle relative to the central propagation axis of light rays exiting said output surface of the central refractive portion in said plane of symmetry on said proximal side of the central propagation axis is equal to or greater than an angular divergence of light rays exiting the distal output surface in said plane of symmetry. 
     
     
         59 . The system of  claim 54 , wherein the optic is positioned relative to the light source such that in the plane of symmetry, a majority of light received through the input surface exits the output surface distal to the central propagation axis.